The Mechanical Handling and Storing of Material

694 THE MECHANICAL HANDLING OF MATERIAL Corliss compound engines of 500 H.P., fed with steam by two Galloway boilers working at 100 lb. pressure. The power for the pneumatic apparatus is provided by two sets of triple-expansion vertical engines of 600 H.P., supplied with steam by three boilers working at a pressure of 160 lb. per square inch. The following operations can be performed simultaneously at the warehouse : 1. Discharging from vessels alongside at the rate of 350 tons per hour. 2. Weighing in tower at the water’s edge. 3. Conveying and distributing into any of the 226 bins. 4. Moving grain about for changing bins or for delivery, and weighing in bulk at the rate of 500 tons per hour. 5. Sacking grain, weighing and loading sacks into forty railway wagons and ten carts. 6. Conveying into barges or coasters at the rate of 150 tons per hour if in bulk, or 250 sacks per hour if sacked. The author is indebted to Mr W. H. Hunter for the illustrations which accompany the above description. The Transit Silos on the Thames.—These form a most interesting group of installations. Although only used as transit silos, they are silos in the fullest sense of the word, and therefore deserve to be mentioned in this chapter. They were built for the old London Grain Elevator Co. by Spencer & Co., Ltd., and are situated on the south side of the Victoria Docks. They consist of four complete and independent installations. The area, of this portion of the Victoria Docks is 50 acres, half of which is water, and the other half land. The space is oblong in shape, and is shown in the plan, Fig. 998. At each end three peninsulas project into the water, thus forming four docks of an area of 2 acres each for the accommodation of the barges. The water in these berths is of sufficient depth to accommodate all ships which can enter the Victoria Docks, so that the largest ships can have their cargo discharged, weighed, or transported into smaller up-river barges, to railway trucks, or into ths large flour mills that have been built there. All these operations can be carried on under cover, and are therefore quite independent of the weather. The four transit silos, two of which are shown in the illustration, Figs. 999 and 1,000 (which also gives explanatory notes), are situated on the south-west and north-west peninsulas, leaving one peninsula for the probable further extension. Each silo-house marked c on the drawing is divided into nine bins or silos, eight of which are used for storage purposes only, whilst the middle space is used for the accommodation of staircases, elevators, etc. Each of the eight silos is 12 ft. square by 80 ft. deep, and has a capacity of 1,000 qrs. of grain. The silos are erected on a massive cast-iron tank forming a cellar, which rests upon a concrete foundation 6 ft. in thickness, the bottom of this tank being 30 ft. below the water level. They are built on the interlaced timber system which has already been described, being formed of “battens” nailed on top of each other, the pieces interlacing. The silo bottoms are so constructed that there are no joins‘in the corners, thus dispensing with rivets at these points, as they are apt to obstruct the flow of the material, and prevent the silos from emptying completely. These silos are supported on rolled steel girders which rest on cast-iron columns. The outside of the granary is covered with corrugated iron, and the roof is covered in a similar manner. The silos are about 100 ft. high, and carry a substantial iron roof which also covers two gas engines for driving the three delivery elevators, one of a capacity of 120 tons per hour, and two of a capacity of 100 tons each per hour. There is no occasion for conveyors, as the elevators which rise above the tops of the silos can readily deposit the grain into any one of them.